The Benefits of Indoor Training for Grand Tour Performance

I've had guys do it twice in a year for the Giro and the Veruelta block of indoor training leading into a grand tour. It's not just we talk about the heat and how it benefits us in performing in hot conditions and mild conditions at the same time there's has been studies released that you find that training indoors with increased cold water temperature actually makes us more efficient in cold weather as well. The science might say this is possible or might say otherwise but you put it in the practice and you see the result yourself, then you start to come up with your own methodology based on what you experienced with your athletes right?